In this book, Lidwien Kapteijns explores how in 1990–91 an armed movement aimed at overthrowing the dictatorship of Siyad Barre morphed into a brutal campaign of ethnic cleansing that plunged Somalia into decades of war and state collapse. Though Kapteijns concludes that the shift in tactics by the United Somali Congress (USC) was driven by political leaders manipulating chauvinistic clan narratives for their own parochial purposes, the body of evidence she marshals also points to a disturbing susceptibility of Somali society circa 1990 not only to embrace clannish hate narratives but to act on them with shocking violence. Kapteijns' conclusions line up with findings from many other zones of ethnic violence – namely, that ethnic/clan cleavages and hatreds were not primordial, but were hardened by years of divide and rule tactics, and then set aflame by power-seeking political and militia figures whose indifference to the terrible human costs of their tactics makes the utter lack of accountability for their actions even harder to accept.

Kapteijns' book is at once important, controversial, unusual and flawed. It is important because it addresses a pivotal moment in the Somali crisis, the period in 1990–91 when the direction of the country hung in the balance, and ultimately swung down an utterly destructive path. Kapteijns' book may not be the last word on the matter, but is the most comprehensive assemblage of evidence from that period that we have, and will enjoy a long shelf life as a result. It also confronts openly the critical question of clan cleansing as an objective of the fighting in 1991, and the powerful taboo in Somali circles over naming names and holding perpetrators to account for the crimes against humanity that occurred in those years. Her insistence on ‘speaking the unspeakable’ gives the book enormous significance in Somali studies.

This also contributes to the controversy surrounding the book. Kapteijns directly confronts and exposes the raw clannish rhetoric and reasoning of the era. The evidence she draws upon to depict strategies of clan cleansing will shock and offend some Somali readers, while others will object on the grounds that the book's reopening of the deep wounds and hate narratives of the era risks re-igniting clan tensions at a time when Somalis are trying to overcome old divisions.

The most vigorous criticisms, however, have already appeared on the internet and condemn the book as a partisan attack on one clan, the Hawiye, which emerged victorious in the capital Mogadishu in 1991. The criticism that the author ‘chose sides’ is not entirely warranted, if one reads the text carefully, but is rooted in the author's choice of time period to study. By focusing on the particular period of 1990–91, Kapteijns steps directly into an ongoing Somali war over history and grievances. As in many other post-war settings, a critical dimension of historical grievance narratives is all about when one begins the story. Many Somali grievances focus on abuses under the Siyad Barre era or even earlier. Kapteijns' focus on the 1990–91 period has the effect of highlighting attention on the Hawiye campaign against Darood citizens. Though the author devotes ample space to the abuses of the Barre regime, Hawiye leaders, by dint of their privileged position of power in the armed liberation movement in 1990 and their capture of the capital, are held responsible for the clan cleansing which engulfed Mogadishu, while the Darood masses are portrayed in that narrow time period as victims. Most Somali and foreign analysts have preferred to embrace a safer, generic position of blaming clannism in general for the terrible losses in 1991–92. Kapteijns hold leaders of all clans accountable for communal violence, but points out that the chauvinistic clan ideology of the victorious Hawiye leaders had far greater long-term consequences and hence bears greater scrutiny. Her observation that high-ranking Hawiye figures in the Barre regime seamlessly shifted to top leadership positions in the USC, where they then demonised the entire Darood clan for complicity in the Barre government, is yet another reminder of the fecklessness of Somali leadership during that critical moment in the country's history.

Parts of the analysis portray the terrible turn toward clan cleansing in Mogadishu as a less organised version of the Interahamwe's orchestrated violence against Tutsi in the Rwandan genocide. Though the author makes clear that what happened in Mogadishu was not genocidal – it was violence aimed to drive an entire clan out of the city, mostly to grab their property and material possessions – the complicity of top political figures in the ethnic purge and pillaging of the city is a deeply disturbing finding.

In the first section, the book draws heavily on Somali poetry from the era to capture Somali sentiments about the crisis. It is an unexpected choice, but Kapteijns makes it work by masterfully contrasting ‘prestigious’ poetry that condemns clannism in safe, general terms, with the ‘non-prestigious’ street poetry designed to attack rival clans and mobilise the poet's lineage.

The book has its share of flaws. The design of the book does not provide a clear introduction to the Somali crisis for a general reader, making much of the text difficult for non-Somali specialists to follow. The insertion of the chapter on Somali poetry at the outset of the book was especially unfortunate in this regard; the material will lose some of its significance for general readers, unless they opt to return to that chapter after completing the book. Analytically, some of the claims in the book are open to contestation or at least refinement. The claim, for instance, that weak social groups in southern Somalia joined in the anti-Darood purge is only partially true – the vast majority of those communities lacked weapons and were the principal victims of repeated looting and assaults by both Hawiye and Darood militias. Likewise, evidence from 1990 demonstrates that the retreating government militia, composed mainly of the clan of President Barre, engaged in collective punishment and scorched earth tactics in Hawiye inhabited zones, needed to be emphasised more. But the author's overall message – that critical decisions made by the USC leadership to turn a liberation movement into a campaign of clan cleansing propelled Somalia into a period of war and division from which it is only now emerging – is an important claim that needs to be explored and considered seriously, not dismissed as an attack on one clan.

An important part of Somali political discourse is claiming victim status – every clan has a powerful grievance narrative that justifies their claim for compensation, land, representation, asylum and more. Intentionally or not, Kapteijns' book provides one clan, the Darood, much more ammunition in its grievance narrative than others, and for that reason will be heavily contested. But the bigger question arising from this book should not be the parochial debate over which clan suffered most and which is most culpable. It is the enduring and troubling question of the lack of any accountability for crimes against humanity that occurred in Somalia – under the Barre regime, in 1991–92, and most recently in the 2011 Somali famine which claimed 260,000 lives. Violence entrepreneurs and their gunmen continue to get away with murder in a land crying out for both peace and justice.